Enameling furnace



Apr-[24, 1923. 4 1,453,051

. F. c. MACKEY ET AL ENAMELING FURNACE Filed Marh 20. 1922 s Sheets-Sheet 1 F. c. MACKEY ET AL ENAMELING FURNACE Filed March 2 3 Sheets-Shet 2 1/1,, if roe/v5 x Afir.24, 1923." 1,453,051

F. C. MACKEY ETAL ENAMELING' FURNACE Filed March 20, 1922 3 Sheets-Sheet 5 w/ wuss; r /A new 7'0/PS T Q C 74 I m M ma,

Patented Apr. 24, 1923.

FEEDER/10:0. .MACKEY AND JQHANN'II. GUMZ, OF CHICAGO, ILLINOIS.

{.P arena ,orrica.

.ENAMELING ,FURNACE.

Application =fi1ed March 20, 1922. Serial Ito-545,159.

To all w 720m it may concern Be it known. that we l nnnnnio C. -MACKEY and J OHANN H. GUMZ, bot-hv citizens. ofthe United States, and residents .of Chicago, county of Cook, and State of Illinoisphave invented certain new and useful sImprovements in Enameling Furnaces, of whichsthe following is a specification.

Our invention relates generally to improvements in enameling :furnaces, but relates more particularly to improvements in furnaces used in the production or manufacture of vitreous enamel ware in which exceedingly high temperatures are required.

The general ob]ect of our invention is to provide a vitreous enameling furnace wherewith a given amount of enamel ware can be produced wlth the consumption of less fuel. Again it is an ob ect of our invention to provide a vitreous enameling furnace wherewith a glven amount of work or materlal can be enameled in less t1me,'1n less space, and

at less cost than is possible with furnaces heretofore devised.

It is also an object of our invention to provide a vitreous enameling furnace of such construction that it will be better adapted to withstand the extremely high'temperatures obtaining in such furnaces, to the end that the cost'of maintenance may bereduced and the periods of continued or uninterrupted service increased. Again with respect to the production of work of certainkinds, it is an object of our invention to provide a furnace wherewith a given amount of material can be produced or enameled in a furnace ofa size much smaller than that required to perform a like amount of work in-furnaces heretOfOre devised.

..Our invention consists generallyin a furnace of th form, arrangement, construction,

proportion. and co-operation of the parts whereby the above named objects, together with others that will appear hereinafter, are attainable; and our invention will be more readily understood byreference to the afoco npanying drawings which illustrate what we'consider, atthe present time, to bathe preferred embodiment thereof.

In a d d a ing F'g.: 1"'s a longitudinal vertical section of :31,furnace embodying our invention viewed am al y s an h line Q e hug. I v V v Fig. 2 is atransverse vertical section substantially along the line 2-2 of Fig. 1.

lEig. 3 is a transverse.longitudinal section substantially on th line 3-3 of Fig. .2, and

.Fig. .4 is a detail sectional view descriptive oftheoperat-ion of the furnace as affecting .the fire brick or lining thereof.

.VVhile the drawings are not accurately drawn to scale they are approximately drawn .to the scale of inches to one foot from whichthe proportions will be more readily ascertainable.

While the furnace shown in the drawings is .aygasfired furnace, liquid .or other fluids maybe employed so that the showing herein shouldzbe taken as by way of illustration and not #by way of limitation.

The size of the furnace, of course, may be varied, but there are certain relative proportions that we deem advisable and even necessary. to maintain, the factors controlling which .will bedeveloped in the detail description hereinafter given.

As will be observed, the furnace is of elongated :form and is composed of vertical outer side walls 1 and 2 .and vertical end walls 3'and 4. These walls may be made of various materials, but are usually made of a non-fire brick. such for example, as red -brick. iVVithin the outer walls will befound an intermediate .filling, usually of an in sulating brick, to which the reference character '5 has been applied.

The combustion space of the furnace proper is defined :by the fire brick lining which is formed to present vertical side walls 6 and 7 and an end wall 8. The other end of the furnace is provided with an opening 9 to permit placement of the work in and removalthereof from thefurnace, this opening being closed by a door or gate ,10 which is provided with an'inner fire brick lining 11. "The: top of the furnace 1-2 is formed in.

fpose t-here is provided-a plurality of burners 13 on one side of the furnace. and a .plu-

rality of burners 14c upon the other side, the burners '14 being staggered or offset with -relationto'the burnerslii. As is well shown,

the burners 13 and 1.4 are provided with inwardly extending nozzle portions 13 and 11, respectively, which terminate in and discharge into openings 15 and 16, respectively, in the fire brick side walls 6 and 7.

l pstanding from the bottom or floor 17 We have formed a plurality of longitudinally extending piers 18, 19, 20, 21 and 22, which extend from end to end of the furnace. These piers are provided with transverse openings 18, 19, 20, 21, and 22, respectively, which are alined with the nozzles 13 and 14 of the fuel burners so that the flames projected by or from the burners can go forward freely under the natural burning act-ion thereof.

By the novel shaping and positioning of the piers 1.8 to 22, inclusive, we are able, in a given size furnace, to provide more piers than can normally be provided pnder the practice heretofore prevailing. As a result, we are able to secure several distinct and important advantages. As will be observed, the various piers, as here shown, are all of substantially the same width, but the spaces between the piers 1S and 19, on the one hand, and 21 and 22 on the other hand, are greater than the spaces between the group of piers 19, 20, and 21. It will also be observed that a shown the piers 18 and 22 are spaced from the side walls a distance substantially equal to the distance between the respective piers of the middle group 19, 20, and 21. This larger number of piers, obviously, provides a larger surface area for exposure to the heat or products of combus tion within the furnace chamber, the advantageous characteristics of which will be more fully developed hereinafter.

The work or material to be enameled is usually placed into the furnace by means of a device known in the trade as a loading fork. In order thatfthe work may be properly supported as it is conveyed into the furnace, this loading fork must be of considerable width and by the spacing of the piers 18 and 19, and 21 and 22, as shown, we areable to accommodate the forks even with the larger number of piers provided. The larger number of piers also provides support for the work at. a. larger number of points, thus eliminating danger of. sagging which is quite likely to occur in other furnaces, particular- 1y where large pieces are being treated.

The side walls, the top, and the bottom of the furnace have been treated in a novel manner whereby we have provided an enor mous surface relative to the cubical capacity or size of the furnace. At, this point, it might be well to recall to mind certain of the objets of our invention, to wit, the object of treating or enameling a given amount of work with less fuel, and the object of providing a furnace construction, which shall minimize those destructive forcesor reactions that cause remature or earl disinte ation of the walls of the furnaces that are subjected to the extremely high temperatures required for vitreous enameling operations. These objects we attain by virtue of the various novel structural characteristics of our furnace, the value of which is increased when. operated in the manner in which we shall now describe;

Before entering upon a description of the operation of the furnace, attention is directed to the large number of pockets 23 that are formed in the side walls,'ends, bottom or floor, and top of the furnace. These pockets are formed by staggering the bricks that form the lining of the furnace, both with respect to the superposed layers or courses and with respect to the innermost plane of the furnace walls. In this manner, an enormous surface is presented to the products of combustion in the furnace, whereby the products of con'i bustion are caused to give off a far greater part of their heat before discharging through the outlets 25 in the top wall or arch 12, than is the case in furnaces heretofore devised.

In the furnace disclosed there are at least 1000 square inches of surface to every square foot of area in the plane parallel to the bottom, i. e., in the area available for the work to be enameled. lVhile the drawings show the furnace as havin only a curved upper wall and straight sides and bottom walls, they may all be curved sothat the terms top, bottom and side walls in the claims should be considered as referring broadly to such genera-l portions of the furnace.

In operation, assuming that the furnace has previously been brought to working temperature and that the furnace is empty, i. e. the work previously enameled has been re moved, the burners 14 and 15 are turned 011, thus producing an intense burning mass within the furnace. The length of time that the burners operate will vary somewhat, depending upon the amount of work being treated, but because of our novel construction the period of operation of the burners can be considerably reduced with the obvious result that less fuel is required. reason why less fuel is required may not at first be apparent, nor will it, at first thought, be obvious thatany other improved result follows from this lesser period of operation and the smaller fuel consumption. characteristics, however, do result from our construction for reasons which we shall now develop.

The burners operate approximately only for a period of from forty to fifty seconds period of firing and the enormous surface of the furnace walls (relative to the cubical The These ,capacityof the furnace), the fire brick is enabled to anddoes absorb a far greater percentage of the heat units-and, atthesame time, this heat does not penetrateas deeply intothe walls ofthe'furnace, thus providing fiat sided constructionthat penetration of the heat would extend much further into the fire brickfbecause it would be necessary to raise the walls through a muchgreaternumber of degreesof temperature in order to store the same number of heat units. When deep penetration exists, it is obvious that the'heat cannot be as quickly and efficiently given off to the work. It should also be "obvious that the furnace wall cannot be raised through a wide temperature change as efficiently as it can be through a relatively low temperature change. Thus we secure both the advantage of confiningthe heat to what may be termed a surface zone and, at-the same tim e ,-the advantage of a more eflicient absorption of the heat generated by the burning fuel., \Ve also secure further important advantages far and above those already stated in that the walls, as a whole, are not raised to as high a temperature, with'the result that they are able to stand up in use for longer periods of time, and what is probably of even greater importance, the difference in temperature between the furnace walls at the time when they have absorbed the heat prior to the placement of the work in the furnace, and the condition thereof after they have given off their heat to the work, is far less than in furnaces heretofore devised; We thereby eliminate one of the most destructive forces operating to destroy or cause disintegration of fire brick, to wit, rapid and great changes in the temperature of the fire brick. The practical result of this. of course. is that our furnace may be operated for longer periods without attention or repair, which is an important advantage when it is considered that enaineling furnaces are usually operated continuously. i. e. twenty-four hours per day.

lVhile it cannot be stated with accuracy, the length of time that the work must remain in the furnace, this will only be for a period of several minutes, and it should be obvious that with our construction the work need not remain as long in the furnace as would otherwise be required. Thus, the operations of enameling are speeded up as well as produced at less cost in fuel outlay and furnace maintenance.

' therein.

The. many advantages of. our furnace will now beapparent to those skilledqin,this..art without further comment.

lVeclaim:

1. An ena'meling ifurnace therein a refractory lining formed with a checkered surface, as and for the purpose specified.

2. An enameling furnace. embodying therein achamber having side walls and top and bottom walls, said side walls having a plurality of recesses therein.

3. An enameling furnace embodying thereina chamber having side walls and'top and bottom walls, said side walls and top havin aplurality of recesses therein.

4. n enameling furnace embodying therein a chamber having side walls andtop and bottom walls, said side walls, top and bottom having aplurality of recesses therein. 1v

:5. An enamelmg furnace embodying therein side walls, top, bottom and .end walls, said walls all having aplurality of recesses 6. An enameling furnace embodying therein a chamber having side walls and 1. An .enameling furnace therein a chamber having side walls andtop and bottom walls, said side walls-and top having a plurality of pockets therein.

8. An enameling furnace embodying therein a chamber having side walls and top and bottom walls, said side walls, top and bottom having a plurality of pockets therein. I

9. An enameling furnace embodying therein side walls, top, bottom and end walls, said walls all having a plurality of pockets therein.

10. An enameling furnace embodying therein a chamber having side walls and top and bottom Walls, said side walls having a plurality of pockets therein, said pockets being formed by courses of firebrick, alternate bricks of every row being spaced inwardly with respect to the others, and the innermost bricks of adjacent courses being offset with respect to those of the first mentioned course.

11. An enameling furnace embodying therein a chamber having side walls and top and bottom walls, said side walls and top having a plurality of pockets therein, said pockets being formed by courses of firebrick, alternate bricks of every row being spaced inwardly with respect to the others, and the innermost bricks of adjacent courses being offset witlfrespect to those of the first mentioned course.

12. An enameling furnace embodying therein a chamber having side walls and top and bottom walls, said side walls, top

embodying top and bottom walls, said side walls.having a plurality of pockets therein.

"' embodying and bottom having a plurality of pockets therein, said pockets being formed by courses of firebrick, alternate bricks of every row being spaced inwardly with respect to the others, and the innermost bricks of adjacent courses being offset with respect to those of the first mentioned course.

13. An enameling furnace embodying therein side walls, top, bottom and end walls, said walls all having a plurality of pockets therein, said pockets being formed by courses of firebrick, alternate bricks of every row being spaced inwardly with respect tothe others, and the innermost bricks of ad jacent courses being offset with respect to those of the first mentioned courses.

14. An enameling furnace having a chamber provided with a bottom wall, a plurality of longitudinally disposed transversely spaced piers therein, said piers including a centrally disposed group, the piers of which are spaced a lesser distance apart than other of the piers.

15. An enameling furnace having a chamber provided with a bottom wall, a plurality of longitudinally disposed transversely spaced piers therein, said piers including a group of three centrally disposed piers, the respective piers of which are spaced a lesser distance apart than other of piers.

16. An enameling furnace having a chamber provided with a bottom wall, a plurality of longitudinally disposed transversely spaced piers upstanding therefrom, said piers including a centrally disposed group, the piers of which are spaced a lesser distance apart than other of the piers and a plurality of recesses formed in the bottom between the said piers.

17. An enameling furnace having a chamber provided with a bottom wall, a plurality of longitudinally disposed transversely spaced piers upstanding therefrom, said piers including a group of three centrally disposed piers, the respective piers;

of which are spaced a lesser distance apart than other of the piers, and a plurality of recesses formed in the bottom between the said piers.

18. The method. of enameling that consists in providing a furnace having a chamber, the walls of which are formed to expose at least 1000 square inches of surface to every square foot of area in a plane parallel to the bottom, i. e. in the area available for the work to be enameled.

In testimony whereof, we have hereunto set our hands, this 9th day of March, 1922.

FREDERIC C. MACKEY. JOHANN H. GUMZ 

